The advent of digital photography encourages users of digital cameras to take large numbers of photographs, this deriving, at least in part, from the fact that such photographs do not require traditional development, with its cost and inconvenience. Digital images are, in contrast, available for use almost immediately, once the film diskette is suitably loaded into a personal computer (PC), or suitable display device.
It is, however, time consuming for the photographer to sort and label these voluminous images, and consequently, the sorting and labelling process is often neglected. As a result, the photographer runs a risk of accumulating a growing number of images, many of which are not readily accessed because of the absence of a convenient method of labelling.
Present methods of automatic identification using image processing are still unsatisfactory, and often cannot detect the presence of any person in an image, let alone a specific person. It is possible, for example, to detect the presence of people in a photograph using detection of skin colour via colour histograms, however this technique is non-specific, and relatively inaccurate.